1. Field of the Invention
The present invention relates to a ringer circuit, particularly to a ringer circuit utilizing an amplifier and comparator circuitry, and more particularly to a ringer circuit utilizing a Push-Pull amplifier and voltage comparators.
2. Description of the Related Art
A ringer circuit is usually utilized in telecommunications terminal equipment, such as telephones and facsimiles, to be activated from an input signal when an incoming call is received. When the ring signal is received at the input of the ringer circuit, the ringer circuit generates an output audio ringer signal, which is heard by the user.
Many conventional ringer circuits are known in the prior art, such as those disclosed in U.S. Pat. Nos. 5,526,418; 5,442,695; 5,111,499; 4,658,419; 4,653,093; and 4,327,254; the contents of which are hereby incorporated by reference herein. These conventional ringer circuits comprise a variety of analog and digital circuits.
However, these ringer circuits have the disadvantage that they often amplify distortion from the input signal in the output ringer signal and tend to be very inefficient. Prior attempts to rectify these disadvantages have resulted in ringer circuits which are complicated in design, and/or expensive to manufacture.
Accordingly, it is an object of the present invention to provide a ringer circuit having low distortion and high gain of the ringer output signal, while having a high efficiency. Moreover, it is still another object of the invention to provide a ringer circuit which is simple in design and inexpensive to manufacture.
Other important objects and advantages of the present invention will be apparent to those of skill in the art based upon the following disclosure, drawings, and claims.